Liquid-phase microextraction of basic drugs - Selection of extraction mode based on computer calculated solubility data

Abstract

The extractability of 58 different basic drugs by 3-phase liquid-phase microextraction (LPME) was studied. Extraction recoveries were correlated to solubility data and log D data calculated with a commercial computer program. The basic drugs were extracted from 1.5 mL water samples (pH 13) through approximately 15 microL of dodecyl acetate immobilized within the pores of a porous polypropylene hollow fibre (organic phase), and into 15 microL of 10 mM HCl (acceptor solution) present inside the lumen of the hollow fibre. Compounds with a calculated solubility below 1 mg/mL at pH 2 were poorly recovered and remained principally in the organic phase. For these drugs, 2-phase LPME may be used as an alternative technique, where the aqueous acceptor phase is replaced by an organic solvent. In the solubility range 1-5 mg/mL, most drugs were effectively extracted (recovery >30%), whereas drugs belonging to the solubility range 5-150 mg/mL were all extracted with recoveries above 30% by 3-phase LPME. The hydrophilic nature of most drugs with solubilities above 150 mg/mL prevented them from entering the organic phase, and only those with log D >1.8 were effectively recovered by 3-phase LPME. For drugs with log D < 1.8 (and solubility >150 mg/mL), carrier-mediated LPME was found to be the preferred technique, where an ion-pair reagent (octanoic acid) was added to the sample. In the case of carrier-mediated LPME, the volume of sample was decreased to 100 microL to facilitate rapid extractions. Based on the present work, the extractability of new compounds may easily be predicted to speed up method development. Extractions were also accomplished from plasma samples, where interactions between proteins and the drugs may reduce the extraction recovery. However, dilution of the plasma samples with water and adjustment of pH into the alkaline region effectively suppressed drug-protein interactions for most of the drugs studied.

Analytical methodologies for the determination of sertraline

“…The extractability of 58 different basic drugs, including SRT, by 3-phase liquid-phase microextraction (LPME) was studied by Pedersen-Bjergaard et al [86]. Extraction recoveries were correlated to solubility data.…”

Hollow fiber-based liquid phase microextraction combined with high-performance liquid chromatography for extraction and determination of some antidepressant drugs in biological fluids

“…These parameters were optimized and finally the system was applied to extract the drugs from the urine and plasma samples. Based on our knowledge Pedersen-Bjergaard et al reported extractability of amitriptyline and sertraline beside 56 of other drugs from water and serum samples [32]. Extraction recoveries were correlated to solubility data and log D data calculated with a commercial computer program.…”

Passive extraction and clean-up of phenoxy acid herbicides in samples from a groundwater plume using hollow fiber supported liquid membranes

“…This extraction mode usually results in sample matrix dependent extraction efficiency and thus calibration difficulty when real samples are analyzed [25,26]. Recently, it was found that this matrix effect can be reduced by performing SLM in complete extraction mode; where the analytes are completely extracted from relatively small amount of sample, e.g.…”